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Articles 1591 - 1620 of 3798

Full-Text Articles in Physical Sciences and Mathematics

Theoretical Estimates Of Spherical And Chromatic Aberration In Photoemission Electron Microscopy, Joseph P. S. Fitzgerald, Robert Campbell Word, Rolf Kӧnenkamp Jan 2016

Theoretical Estimates Of Spherical And Chromatic Aberration In Photoemission Electron Microscopy, Joseph P. S. Fitzgerald, Robert Campbell Word, Rolf Kӧnenkamp

Physics Faculty Publications and Presentations

We present theoretical estimates of the mean coefficients of spherical and chromatic aberration for low energy photoemission electron microscopy (PEEM). Using simple analytic models, we find that the aberration coefficients depend primarily on the difference between the photon energy and the photoemission threshold, as expected. However, the shape of the photoelectron spectral distribution impacts the coefficients by up to 30%. These estimates should allow more precise correction of aberration in PEEM in experimental situations where the aberration coefficients and precise electron energy distribution cannot be readily measured.

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Atmospheric Methane Isotopic Record Favors Fossil Sources Flat In 1980s And 1990s With Recent Increase, Andrew L. Rice, Christopher Butenhoff, Doaa Galal Mohammed Teama, Florian H. Roger, M. A. K. Khalil, R. A. Rasmussen Jan 2016

Atmospheric Methane Isotopic Record Favors Fossil Sources Flat In 1980s And 1990s With Recent Increase, Andrew L. Rice, Christopher Butenhoff, Doaa Galal Mohammed Teama, Florian H. Roger, M. A. K. Khalil, R. A. Rasmussen

Physics Faculty Publications and Presentations

Observations of atmospheric methane (CH4) since the late 1970s and measurements of CH4 trapped in ice and snow reveal a meteoric rise in concentration during much of the twentieth century. Since 1750, levels of atmospheric CH4 have more than doubled to current globally averaged concentration near 1,800 ppb. During the late 1980s and 1990s, the CH4 growth rate slowed substantially and was near or at zero between 1999 and 2006. There is no scientific consensus on the drivers of this slowdown. Here, we report measurements of the stable isotopic composition of atmospheric CH4 (13C/12C and D/H) from a rare air …

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Madagascar’S Mangroves: Quantifying Nation-Wide And Ecosystem Specific Dynamics, And Detailed Contemporary Mapping Of Distinct Ecosystems, Trevor G. Jones, Leah Glass, Samir Gandhi, Lalao Ravaoarinorotsihoarana, Aude Carro, Lisa Benson, Harifidy Rakoto Ratsimba, Chandra Giri, Dannick Randriamanatena, Garth Cripps Jan 2016

Madagascar’S Mangroves: Quantifying Nation-Wide And Ecosystem Specific Dynamics, And Detailed Contemporary Mapping Of Distinct Ecosystems, Trevor G. Jones, Leah Glass, Samir Gandhi, Lalao Ravaoarinorotsihoarana, Aude Carro, Lisa Benson, Harifidy Rakoto Ratsimba, Chandra Giri, Dannick Randriamanatena, Garth Cripps

Environmental Science and Management Faculty Publications and Presentations

Mangrove ecosystems help mitigate climate change, are highly biodiverse, and provide critical goods and services to coastal communities. Despite their importance, anthropogenic activities are rapidly degrading and deforesting mangroves world-wide. Madagascar contains 2% of the world’s mangroves, many of which have undergone or are starting to exhibit signs of widespread degradation and deforestation. Remotely sensed data can be used to quantify mangrove loss and characterize remaining distributions, providing detailed, accurate, timely and updateable information. We use USGS maps produced from Landsat data to calculate nation-wide dynamics for Madagascar’s mangroves from 1990 to 2010, and examine change more closely by partitioning …

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Three Simple Experiments To Examine The Effect Of Sediment Pollution On Algae-Based Food Webs In Streams, Patrick M. Edwards, Rodney Shroufe Jan 2016

Three Simple Experiments To Examine The Effect Of Sediment Pollution On Algae-Based Food Webs In Streams, Patrick M. Edwards, Rodney Shroufe

Environmental Science and Management Faculty Publications and Presentations

Streams and stream macroinvertebrates are ideal natural systems for ecological inquiry. We present three simple experiments that students can use to conduct field-based investigations which illustrate the importance of algae-based food webs in streams and measure the effects of sediment pollution (scour and deposition) on stream ecological processes. Over the past 5 years, we have conducted these experiments 19 times with our students. We report on the results and reliability of these experiments and make suggestions for other educators who may want to conduct them.

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Resident Perceptions Of Natural Resources Between Cities And Across Scales In The Pacific Northwest, Anita T. Morzillo, Betty J. Kreakie, Noelwah R. Netusil, J. Alan Yeakley Jan 2016

Resident Perceptions Of Natural Resources Between Cities And Across Scales In The Pacific Northwest, Anita T. Morzillo, Betty J. Kreakie, Noelwah R. Netusil, J. Alan Yeakley

Environmental Science and Management Faculty Publications and Presentations

As the global population becomes increasingly urban, research is needed to explore how local culture, land use, and policy will influence urban natural resource management. We used a broad-scale comparative approach and survey of residents within the Portland (Oregon)-Vancouver (Washington) metropolitan areas, USA, two states with similar geographical and ecological characteristics, but different approaches to land-use planning, to explore resident perceptions about natural resources at three scales of analysis: property level (“at or near my house”), neighborhood (“within a 20-minute walk from my house”), and metro level (“across the metro area”). At the metro-level scale, nonmetric multidimensional scaling revealed that …

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Worldview-Based Scenarios Highlight Stakeholder Values And Assumptions, John Rueter Jan 2016

Worldview-Based Scenarios Highlight Stakeholder Values And Assumptions, John Rueter

Environmental Science and Management Faculty Publications and Presentations

In lake management, we have the privilege and responsibility to work with the public on highly visible resources. Everybody has an opinion based on his or her personal values and observations. While we might sometimes consider this plethora of value statements as the bane of our existence, we all realize that public engagement is crucial for the health and future of lakes. Poor lake health is often caused by many little insults that stem from a wide range of legitimate views for how the lake should be treated as a resource. We need a framework to be able to deal …

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Signal Velocity In Oscillator Arrays, Carlos E. Cantos, David K. Hammond, J. J. P. Veerman Jan 2016

Signal Velocity In Oscillator Arrays, Carlos E. Cantos, David K. Hammond, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

We investigate a system of coupled oscillators on the circle, which arises from a simple model for behavior of large numbers of autonomous vehicles. The model considers asymmetric, linear, decentralized dynamics, where the acceleration of each vehicle depends on the relative positions and velocities between itself and a set of local neighbors. We first derive necessary and sufficient conditions for asymptotic stability, then derive expressions for the phase velocity of propagation of disturbances in velocity through this system. We show that the high frequencies exhibit damping, which implies existence of well-defined signal velocities c+>0 and c−f(x−c+t) in the direction …

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Mangrove Enhancement As A Climate Change Adaptation Strategy In The Republic Of The Marshall Islands (Rmi): Potential Ecosystem Service Shifts Following Colonization, Andrew S. Harwood Jan 2016

Mangrove Enhancement As A Climate Change Adaptation Strategy In The Republic Of The Marshall Islands (Rmi): Potential Ecosystem Service Shifts Following Colonization, Andrew S. Harwood

Environmental Science and Management Professional Master's Project Reports

The ability of Small Island Developing States (SIDS) and Pacific Island communities to adapt to the increasing sea-levels, storm surge, saltwater intrusion, and other threats posed by global climate change is critical to the survival of many of these local communities as well as their cultures (LivingIslands.org). One of the world’s most striking examples of a nation at great risk is the Republic of the Marshall Islands (RMI) in the central Pacific Ocean. Due to a combination of factors, including the country’s extremely low elevation above sea-level (an average of 2 meters) and lack of adequate structures to provide safety …

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Management Plan For Western Painted Turtle (Chrysemys Picta Belli) At Fairview Creek Headwaters, Ashley Smithers Jan 2016

Management Plan For Western Painted Turtle (Chrysemys Picta Belli) At Fairview Creek Headwaters, Ashley Smithers

Environmental Science and Management Professional Master's Project Reports

Western painted turtles (Chrysemys picta belli) are found occupying Fairview Creek Headwaters (FCH) in Gresham, Oregon. This urban stream contains a large wetland with an adjacent butte, all managed by the City of Gresham. This management plan addresses the preferred habitat and population of turtles at the site. A habitat delineation of the site revealed specific locations where habitat improvements could take place as well as areas of already beneficial habitat. Two site plans were prepared showing areas of the site that could be enhanced with nesting habitat as well as additional aquatic habitat and basking habitat. A habitat study …

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Oxyhalogen-Sulfur Chemistry: Kinetics And Mechanism Of Oxidation Of N-Acetylthiourea By Aqueous Bromate And Acidified Bromate, Kudzanai Chipiso, Wilbes Mbiya, Thai Tran, Reuben H. Simoyi Jan 2016

Oxyhalogen-Sulfur Chemistry: Kinetics And Mechanism Of Oxidation Of N-Acetylthiourea By Aqueous Bromate And Acidified Bromate, Kudzanai Chipiso, Wilbes Mbiya, Thai Tran, Reuben H. Simoyi

Chemistry Faculty Publications and Presentations

The oxidation of N-acetylthiourea (ACTU) by acidic bromate has been studied by observing formation of bromine in excess bromate conditions. The reaction displays an induction period before formation of bromine. The stoichiometry of the reaction was determined to be 4:3: 4BrO 3 – +3(CH 3 CO)NH(NH 2 )C=S+3H 2 O®4Br – +3(CH 3 CO)NH(NH 2 )C=O+3SO 4 2– +6H + (A) with a complete desulfurization of ACTU to its urea analogue. In excess bromate conditions the stoichiometry was 8:5: 8BrO 3 – + 5(CH 3 CO)NH(NH 2 )C=S + H 2 O ® 4Br 2 + 5(CH 3 CO)NH(NH 2 …

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Electrochemistry-Coupled To Mass Spectrometry In Simulation Of Metabolic Oxidation Of Methimazole: Identification And Characterization Of Metabolites, Kudzanai Chipiso, Reuben H. Simoyi Jan 2016

Electrochemistry-Coupled To Mass Spectrometry In Simulation Of Metabolic Oxidation Of Methimazole: Identification And Characterization Of Metabolites, Kudzanai Chipiso, Reuben H. Simoyi

Chemistry Faculty Publications and Presentations

Methimazole (MMI), an antithyroid drug, is associated with idiosyncratic toxicity. Reactive metabolites resulting from bioactivation of the drug have been implicated in these adverse drug reactions. Mimicry of enzymatic oxidation of MMI was carried out by electrochemically oxidizing MMI using a coulometric flow-through cell equipped with a porous graphite working electrode. The cell was coupled on-line to electrospray ionization mass spectrometry (EC/ESI-MS). ESI spectra were acquired in both negative and positive modes. In acidic medium, ESI spectral analysis showed that the dimer was the main product, while in neutral and basic media, methimazole sulfenic acid, methimazole sulfinic acid and methimazole …

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The Conflict Resolution Case Study In Urban Life: Bull Run Watershed Case, Chang-Yu Hong Jan 2016

The Conflict Resolution Case Study In Urban Life: Bull Run Watershed Case, Chang-Yu Hong

Geography Faculty Publications and Presentations

The City of Portland and the United States Department of Agriculture (USDA) Forest Service are working together, along with citizens, to formulate a comprehensive new policy to guide joint management of the Bull Run watershed at Mt. Hood National Forest. This process has brought about four decades of conflict, resulting from differences between the federal view of multiple use and the local view of exclusive use for producing high quality water. The new policy is being formulated by the City of Portland and the Forest Service through negotiation of a comprehensive Memorandum of Understanding that structures the parties’ roles, responsibilities, …

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Tridiagonal Matrices And Boundary Conditions, J. J. P. Veerman, David K. Hammond Jan 2016

Tridiagonal Matrices And Boundary Conditions, J. J. P. Veerman, David K. Hammond

Mathematics and Statistics Faculty Publications and Presentations

We describe the spectra of certain tridiagonal matrices arising from differential equations commonly used for modeling flocking behavior. In particular we consider systems resulting from allowing an arbitrary boundary condition for the end of a one-dimensional flock. We apply our results to demonstrate how asymptotic stability for consensus and flocking systems depends on the imposed boundary condition.

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Full State Revivals In Linearly Coupled Chains With Commensurate Eigenspectra, J. J. P. Veerman, Jovan Petrovic Jan 2016

Full State Revivals In Linearly Coupled Chains With Commensurate Eigenspectra, J. J. P. Veerman, Jovan Petrovic

Mathematics and Statistics Faculty Publications and Presentations

Coherent state transfer is an important requirement in the construction of quantum computer hardware. The state transfer can be realized by linear next-neighbour-coupled finite chains. Starting from the commensurability of chain eigenvalues as the general condition of periodic dynamics, we find chains that support full periodic state revivals. For short chains, exact solutions are found analytically by solving the inverse eigenvalue problem to obtain the coupling coefficients between chain elements. We apply the solutions to design optical waveguide arrays and perform numerical simulations of light propagation thorough realistic waveguide structures. Applications of the presented method to the realization of a …

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A Multivariate Nonlinear Mixed Effects Model For Longitudinal Image Analysis: Application To Amyloid Imaging, Murat Bilgel, Jerry L. Prince, Dean F. Wong, Susan M. Resnick, Bruno M. Jedynak Jan 2016

A Multivariate Nonlinear Mixed Effects Model For Longitudinal Image Analysis: Application To Amyloid Imaging, Murat Bilgel, Jerry L. Prince, Dean F. Wong, Susan M. Resnick, Bruno M. Jedynak

Mathematics and Statistics Faculty Publications and Presentations

It is important to characterize the temporal trajectories of disease-related biomarkers in order to monitor progression and identify potential points of intervention. These are especially important for neurodegenerative diseases, as therapeutic intervention is most likely to be effective in the preclinical disease stages prior to significant neuronal damage. Neuroimaging allows for the measurement of structural, functional, and metabolic integrity of the brain at the level of voxels, whose volumes are on the order of mm3. These voxelwise measurements provide a rich collection of disease indicators. Longitudinal neuroimaging studies enable the analysis of changes in these voxelwise measures. However, …

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Voxel Based Morphometry In Optical Coherence Tomography: Validation & Core Findings, Bhavna J. Antony, Min Chen, Aaron Carass, Bruno M. Jedynak, Omar Al-Louzi, Sharon D. Solomon, Shiv Saidha, Peter Calabresi, Jerry L. Prince Jan 2016

Voxel Based Morphometry In Optical Coherence Tomography: Validation & Core Findings, Bhavna J. Antony, Min Chen, Aaron Carass, Bruno M. Jedynak, Omar Al-Louzi, Sharon D. Solomon, Shiv Saidha, Peter Calabresi, Jerry L. Prince

Mathematics and Statistics Faculty Publications and Presentations

Optical coherence tomography (OCT) of the human retina is now becoming established as an important modality for the detection and tracking of various ocular diseases. Voxel based morphometry (VBM) is a long standing neuroimaging analysis technique that allows for the exploration of the regional differences in the brain. There has been limited work done in developing registration based methods for OCT, which has hampered the advancement of VBM analyses in OCT based population studies. Following on from our recent development of an OCT registration method, we explore the potential benefits of VBM analysis in cohorts of healthy controls (HCs) and …

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High-Resolution Ground-Penetrating Radar Profiles Of Perennial Lake Ice In The Mcmurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, And Subbottom, Hilary A. Dugan, Steven A. Arcone, Maciej K. Obryk, Peter T. Doran Jan 2016

High-Resolution Ground-Penetrating Radar Profiles Of Perennial Lake Ice In The Mcmurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, And Subbottom, Hilary A. Dugan, Steven A. Arcone, Maciej K. Obryk, Peter T. Doran

Geology Faculty Publications and Presentations

Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces. Our goal was to find further information on the origin of the deposition and formation of intra-ice layers, bottom topography, and subbottom deposits using GPR with pulses centered near 850 MHz on two permanently ice-covered lakes in the Mc- Murdo Dry Valleys, Antarctica. The profiles were obtained using a one-person sled operation over …

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Response Of Antarctic Cryoconite Microbial Communities To Light, Elizabeth A. Bagshaw, Jemma L. Wadham, Martyn Tranter, Rupert Perkins, Alistair Morgan, Christopher J. Williamson, Andrew G. Fountain, Sean Fitzsimons, Ashley Dubnick Jan 2016

Response Of Antarctic Cryoconite Microbial Communities To Light, Elizabeth A. Bagshaw, Jemma L. Wadham, Martyn Tranter, Rupert Perkins, Alistair Morgan, Christopher J. Williamson, Andrew G. Fountain, Sean Fitzsimons, Ashley Dubnick

Geology Faculty Publications and Presentations

Microbial communities on polar glacier surfaces are found dispersed on the ice surface, or concentrated in cryoconite holes and cryolakes, which are accumulations of debris covered by a layer of ice for some or all of the year. The ice lid limits the penetration of photosynthetically available radiation (PAR) to the sediment layer, since the ice attenuates up to 99% of incoming radiation. This suite of field and laboratory experiments demonstrates that PAR is an important control on primary production in cryoconite and cryolake ecosystems. Increased light intensity increased efficiency of primary production in controlled laboratory incubations of debris from …

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Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey Dec 2015

Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey

Dissertations and Theses

In November 2006 a Pineapple Express rainstorm moved through the Pacific Northwest generating record precipitation, 22 to 50 cm in the two-day event on Mt. Rainier. Copeland (2009) and Legg (2013) identified debris flows in seven drainages in 2006; Inter Fork, Kautz, Ohanapecosh, Pyramid, Tahoma, Van Trump, and West Fork of the White River. This study identified seven more drainages: Carbon, Fryingpan, Muddy Fork Cowlitz, North Puyallup, South Mowich, South Puyallup, and White Rivers. Twenty-nine characteristics, or attributes, associated with the drainages around the mountain were collected. Thirteen were used in a regression analysis in order to develop a susceptibility …

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A Method For Achieving Analytic Formulas For Three Body Integrals Consisting Of Powers And Exponentials In All Three Interparticle Hyllerass Coordinates, Chris M. Keating Dec 2015

A Method For Achieving Analytic Formulas For Three Body Integrals Consisting Of Powers And Exponentials In All Three Interparticle Hyllerass Coordinates, Chris M. Keating

Dissertations and Theses

After an introduction to the variational principle of three body systems via the Helium atom, we present general analytical formulas for the radial parts of integrals that occur when three body systems are described using wave functions that consist of powers and exponentials in all three interparticle Hylleraas coordinates [Hylleraas1929]. This work is an extension of integrals given by Harris, Frolov and Smith, Jr. [Harris2004]. Specifically included are radial integrals encountered in calculations involving the dipole moment matrix element in Hylleraas coordinates that contain a function f(kr1) (such as a spherical Bessel function) in addition to …

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Analysis Of Capillary Flow In Interior Corners : Perturbed Power Law Similarity Solutions, Joshua Thomas Mccraney Dec 2015

Analysis Of Capillary Flow In Interior Corners : Perturbed Power Law Similarity Solutions, Joshua Thomas Mccraney

Dissertations and Theses

The design of fluid management systems requires accurate models for fluid transport. In the low gravity environment of space, gravity no longer dominates fluid displacement; instead capillary forces often govern flow. This thesis considers the redistribution of fluid along an interior corner. Following a rapid reduction of gravity, fluid advances along the corner measured by the column length z = L(t), which is governed by a nonlinear partial differential equation with dynamical boundary conditions. Three flow types are examined: capillary rise, spreading drop, and tapered corner. The spreading drop regime is shown to exhibit column length growth L ~ …

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Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner Dec 2015

Dendrochronology And Middle Miocene Petrified Oak: Modern Counterparts And Interpretation, William E. Wright, Martin J. Streck, Christopher Baisan, W. Walton Wright, Paul Szejner

Geology Faculty Publications and Presentations

This study reports the first successful statistical crossdating among many ring width time series from petrified wood, thus providing a replicable continuous annual resolution window into tree growth and environmental influences during the middle Miocene. The petrified samples, of the genus Quercus, originated at the Stinking Water (SW) locality in Oregon, a Miocene-aged exposure associated with the Columbia River Basalts. 40AR/39AR dating on pillow basalt from the locality yielded a weighted Plateau Age of 13.79 ±0.09 Ma placing the death of the trees at the end of the Langhian Stage of the Middle Miocene (15.97±0.05 to 13.65±0.05 …

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From Boolean Equalities To Constraints, Sergio Antoy, Michael Hanus Dec 2015

From Boolean Equalities To Constraints, Sergio Antoy, Michael Hanus

Computer Science Faculty Publications and Presentations

Although functional as well as logic languages use equality to discriminate between logically different cases, the operational meaning of equality is different in such languages. Functional languages reduce equational expressions to their Boolean values, True or False, logic languages use unification to check the validity only and fail otherwise. Consequently, the language Curry, which amalgamates functional and logic programming features, offers two kinds of equational expressions so that the programmer has to distinguish between these uses. We show that this distinction can be avoided by providing an analysis and transformation method that automatically selects the appropriate operation. Without this distinction …

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Engineering A Healthier Watershed: Middle School Students Use Engineering Design To Lessen The Impact Of Their Campus' Impervious Surfaces On Their Local Watershed, Elizabeth Claire Gardner Dec 2015

Engineering A Healthier Watershed: Middle School Students Use Engineering Design To Lessen The Impact Of Their Campus' Impervious Surfaces On Their Local Watershed, Elizabeth Claire Gardner

Dissertations and Theses

It is important that students understand not only how their local watershed functions, but also how it is being impacted by impervious surfaces. Additionally, students need experience exploring the scientific and engineering practices that are necessary for a strong STEM background. With this knowledge students can be empowered to tackle this real and local problem using engineering design, a powerful practice gaining momentum and clarity through its prominence in the recent Framework for K-12 Science Education. Twenty classes of suburban sixth-graders participated in a new five-week Watershed Engineering Design Unit taught by their regular science teachers. Students engaged in scientific …

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Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray Dec 2015

Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray

Dissertations and Theses

Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved. …

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The Performance Of Random Prototypes In Hierarchical Models Of Vision, Kendall Lee Stewart Dec 2015

The Performance Of Random Prototypes In Hierarchical Models Of Vision, Kendall Lee Stewart

Dissertations and Theses

I investigate properties of HMAX, a computational model of hierarchical processing in the primate visual cortex. High-level cortical neurons have been shown to respond highly to particular natural shapes, such as faces. HMAX models this property with a dictionary of natural shapes, called prototypes, that respond to the presence of those shapes. The resulting set of similarity measurements is an effective descriptor for classifying images. Curiously, prior work has shown that replacing the dictionary of natural shapes with entirely random prototypes has little impact on classification performance. This work explores that phenomenon by studying the performance of random prototypes on …

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Next-Generation Scientists Get A Taste Of Their Future Careers, Patrick M. Edwards, Linda A. George, Matthew Mctammany Dec 2015

Next-Generation Scientists Get A Taste Of Their Future Careers, Patrick M. Edwards, Linda A. George, Matthew Mctammany

Environmental Science and Management Faculty Publications and Presentations

Article provides an overview of the middle and high school poster session that took place during the 2014 Joint Aquatic Sciences Meeting (JASM) in Portland, Oregon. The poster session provided the students with opportunity to participate in the research process and prepare their posters.

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Integrating Freight Into Livable Communities, Kristine M. Williams, Alexandria Carroll Dec 2015

Integrating Freight Into Livable Communities, Kristine M. Williams, Alexandria Carroll

TREC Final Reports

Where livability is a goal of the planning process, freight runs the risk of not being considered except as an afterthought or as something to be excluded. Yet, freight is an integral part of local economic development. Because economic prosperity is a key characteristic of livable communities, freight must be incorporated into the planning process. This study explores the relationship between freight and livability through a comprehensive literature review and case study research. The final report includes a menu of strategies and case study perspectives that highlight the importance of transportation and land use integration, interagency coordination, and context-sensitivity in …

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Exploring, Exploiting And Evolving Diversity Of Aquatic Ecosystem Models: A Community Perspective, Annette B.G. Janssen, George B. Arhonditsis, Arthur Beusen, Karsten Bolding, Louise Bruce, Jorn Bruggeman, Raoul-Marie Couture, Andrea S. Downing, J. Alex Elliott, Marieke A. Frassl, Gideon Gal, Daan J. Gerla, Matthew R. Hipsey, Fenjuan Hu, Stephen C. Ives, Jan H. Janse, Erik Jeppesen, Klaus D. Jöhnk, David Kneis, Xiangzhen Kong, Jan J. Kuiper, Moritz K. Lehmann, Carsten Lemmen, Deniz Özkundakci, Thomas Petzoldt, Karsten Rinke, Barbara J. Robson, René Sachse, Sebastiaan A. Schep, Martin Schmid, Huub Scholten, Sven Teurlincx, Dennis Trolle, Tineke A. Troost, Anne A. Van Dam, Luuk P.A. Van Gerven, Mariska Weijerman, Scott A. Wells, Wolf M. Mooij Dec 2015

Exploring, Exploiting And Evolving Diversity Of Aquatic Ecosystem Models: A Community Perspective, Annette B.G. Janssen, George B. Arhonditsis, Arthur Beusen, Karsten Bolding, Louise Bruce, Jorn Bruggeman, Raoul-Marie Couture, Andrea S. Downing, J. Alex Elliott, Marieke A. Frassl, Gideon Gal, Daan J. Gerla, Matthew R. Hipsey, Fenjuan Hu, Stephen C. Ives, Jan H. Janse, Erik Jeppesen, Klaus D. Jöhnk, David Kneis, Xiangzhen Kong, Jan J. Kuiper, Moritz K. Lehmann, Carsten Lemmen, Deniz Özkundakci, Thomas Petzoldt, Karsten Rinke, Barbara J. Robson, René Sachse, Sebastiaan A. Schep, Martin Schmid, Huub Scholten, Sven Teurlincx, Dennis Trolle, Tineke A. Troost, Anne A. Van Dam, Luuk P.A. Van Gerven, Mariska Weijerman, Scott A. Wells, Wolf M. Mooij

Civil and Environmental Engineering Faculty Publications and Presentations

Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity by comparing and combining different aspects of …

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The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2015, David J. Lauten, Kathleen A. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines Dec 2015

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2015, David J. Lauten, Kathleen A. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines

Institute for Natural Resources Publications

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 3 April – 11 September 2015. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2015 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine …

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